1. Field of the Invention
The present invention relates to diapers; and, more particularly, to a diaper system wherein a plurality of diapers comprising an inner diaper and an outer diaper are attached to each other so that the soiled inner diaper may be readily removed to thereby expose a fresh outer diaper.
2. Description of the Prior Art
A number of prior art patents relate to the use of multiple layered diapers. These multiple layers allow improved absorption of liquids and do not constitute separate diapers. Liquid retaining capacity is oftentimes absent, since the strength and size these multiple layered diapers is generally inadequate to meet the required level of urine absorption.
U.S. Pat. No. 4,022,210 to Glassman discloses a disposable diaper having a supplemental insert. This disposable diaper has a removable laminated supplemental insert formed with a pull tab to permit its separation from the diaper. Both the diaper and insert have means to insure spreading of any moisture deposited thereon. The insert also includes means to initially hold the margins of the diaper folded. Due to the small size of the insert, the liquid discharged by the baby tends to overwhelm the liquid capturing capacity of the insert. The insert does not contain moisture absorption superabsorbers and therefore has only limited fluid absorption capability. The underlying diaper may therefore be soiled and removal of the insert does not guarantee a fresh diaper underneath.
U.S. Pat. No. 4,265,245 to Glassman discloses a double-duty diaper. This diaper comprises a main diaper having an outer layer of water impervious material and a body contacting inner layer of moisture absorbent material, such as starch. It also includes a removable insert strip arranged on the body contacting surface of the main diaper, capable of absorbing moisture and retaining loose excrement. The insert strip includes moisture proof bottom layer with extensions, which may be manipulated to prevent lateral overflow of moisture and excrement prior to and during removal of the soiled insert strip from the main diaper. The main diaper is such that it can be used without the insert and it also includes means to cover wastes therein while being removed from the body. Due to the small size of the insert, the liquid discharged by the baby tends to overwhelm the liquid capturing capacity of the insert. The plastic flaps provided occupy the area surrounding the small insert and do not provide moisture absorption capability. Their function is restricted to wrapping the removed insert. The insert does not contain moisture absorption superabsorbers. It has limited fluid absorption capability, with the result that the underlying diaper is frequently soiled. Accordingly, removal of the insert does not guarantee a fresh diaper underneath.
U.S. Pat. No. 4,838,885 to Bernardin discloses form-fitting self-adjusting disposable garment with a multilayered absorbent. This anatomically form-fitting, self-adjusting disposable garment has a stretchable outer cover. It provides fixed position fasteners and a multilayered absorbent structure. The multilayered absorbent structure has a liquid permeable body-side liner, a liquid impermeable barrier and an absorbent composite disposed between the liner and the barrier. The absorbent composite comprises a uniform composition of fluff or a mixture of a hydrogel and absorbent material. It may alternatively comprise a first and second layer of absorbent materials differing in densities or differing by pore sizes. The absorbent composite can further comprise a mixture of a hydrogel and a filler material, which may be a hydrophilic or hydrophobic material treated with a surfactant. The absorbent composite is not a diaper. Rather, it comprises an insert positioned within a disposable garment. The multilayered absorbent material is a single element with a liquid permeable covering on the body contacting side and a liquid impermeable barrier layer on the garment contacting side.
U.S. Pat. No. 4,892,598 to Stevens, et al. discloses a method of integrating an absorbent insert into an elastomeric outer cover of a diaper garment. This method integrates a fluid-absorbing component into a holding component of an anatomically form-fitting, generally self-adjusting absorbent garment. An elastomeric outer cover is provided for holding a relatively inelastic absorbent insert in selected bodily registration for absorbing and containing bodily fluids. A slidable hem retaining arrangement connects the insert to the outer cover. This arrangement includes cooperating fasteners that engage with one another through a plurality of fenestrations, allowing unrestricted elongation or retraction of the outer cover relative to the insert. The fasteners are releasably engageable with one another to allow removal and replacement of the insert when soiled. Alternatively, ultrasonic bonds may be used instead of refastenable closures, where a single-use disposable garment is produced. The elastomeric outer cover receives the fluid absorbing component. The diaper garment does not contain multiple diapers. It must be physically removed to replace the absorbent component.
U.S. Pat. No. 5,217,447 to Gagnon discloses a diaper system with detachable linings. This diaper assembly includes a reusable over-garment having opposite side edges and two opposite ends and inner and outer surfaces. An absorbent liner is adapted for positioning on the inner surface side of the over-garment. This liner also has opposite ends and inner and outer surfaces. There is a separate, disposable non-absorbent inner sheet adapted to cover the inner surface of the liner. Snap fasteners are provided for detachably connecting the opposite ends of both the liner and the inner sheet to respective opposite ends of the garment to enhance stability. A moisture proof sheet is disposed on the inner surface of the over-garment and this sheet has elasticized side edges. The replaceable liner is a single absorber positioned within the over-garment. The over-garment has to be first removed to replace the lining. The lining has no barrier on the side that contacts the outer-garment and, as a result, moisture proof sheet are utilized to prevent soiling of the over-garment. If the liner absorption capability is completely exhausted, the over-garment will become soiled.
U.S. Pat. No. 5,342,340 to Kichefski, et al. a discloses reusable diaper. This reusable leakproof diaper is said to be as convenient in use as a disposable diaper. It includes a one-or-more layered absorbent rectangular liner attached by strips of liquid impervious material to a liquid impervious outer shell. A closure system, such as snap fasteners, single looped closures, buttons, or hooks is mounted on the outer shell. The sides of the outer shell include elastic strips along the portion of the shell that forms a leg opening when the diaper is in use. The unique design for attaching the inner absorbent liner to the liquid impervious outer shell provides the diaper with improved resistance to leakage. This diaper is appointed for control of incontinence; and is not a baby diaper. The multiple absorbent layers are juxtaposed together. They are not individually removed to expose a fresh unsoiled liner.
U.S. Pat. No. 5,720,738 to Clark discloses an edge-protected, layered, absorbent product. This multilayered absorbent feminine hygiene product, which is configured for releasable attachment to a user's garment, has a plurality of absorbent pads. Each of the absorbent pads has an absorbent layer to contain absorbed fluid and a barrier layer to prevent absorbed fluid from leaking completely through the individual pad. The pads are releasably attached along at least a portion of their lateral edges with a protective material. The protective material protects unexposed absorbent pad layers from soiling by fluid runoff from the exposed pad layer. It contributes to the attachment strength between the layers during use. This product is a feminine hygiene product and is not a baby diaper. The plurality of pads used merely provide additional protection. Removal of the topmost soiled pad does not expose an unsoiled pad.
U.S. Pat. No. 5,725,518 to Coates discloses a reusable diaper having a gusseted pad insert. This reusable infant or adult diaper comprises a fluid absorbent pad on the inner surface of a waterproof, hourglass-shaped, diaper shell. A pair of fastener tabs extends from the rear corners of the diaper shell carrying filamentary hook fastener material. Slightly larger strips of filamentary loop material on the inner surface of the diaper shell cover the fastener tabs during washing to protect the filamentary hook material from buildup of lint. Each fastener tab and its cover, assembled to the diaper shell by a single continuous line of stitching and turned to the inside of the diaper, present a finished edge at a corner of the diaper shell. The diaper is fitted to the infant or adult by wrapping the shell around the pelvic region and coupling the fastener tabs to a pair of strips carrying filamentary loop material and arranged in a V-pattern on the front of the diaper. Several different mechanisms fasten the shell and absorbent material to the body of the wearer. Absorbent material may be sewn into the shell or be floating in the shell between the leg holes of the diaper. The absorbent material forms a single element which, when soiled, must be discarded. No means are provided to expose the soiled absorbent pad, or to pull it away to expose a fresh absorbent pad.
U.S. Pat. No. 6,114,597 to Romare discloses an absorbent product for receiving body fluids. This absorbent product, such as a sanitary napkin, a panty liner, an incontinence protector, or the like, is arranged in the crotch region of a user in order to collect and absorb discharged body fluids. Means are provided for fastening the diaper inside a pair of underpants. The product has a principally elongated shape with a longitudinal centerline and a transverse centerline. The upper part of the product faces towards the user and a lower part of the product faces away from the user. The upper and lower parts are mutually joined, so that each has a front part facing forwardly towards the abdomen of a user while the rear part faces rearwardly towards the behind of the user. The upper part and the lower part further each have a front transverse edge and a rear transverse edge, as well as two longitudinal side edges extending between the two transverse edges. The upper part and the lower part are mutually joined only at the acquisition zone of the product, which is the region of the product which is intended to first be wetted by body fluid. The upper part surrounding the entire periphery of the acquisition zone is free from connections to the lower part. This product is not a diaper; the body fluid absorption member is an elongated body. The lower part of the absorber has a barrier, and is removably attached to inside of underpants. The absorber cannot be removed and new one reattached without first removing the underpants.
U.S. Pat. No. 6,193,702 to Spencer discloses, in combination, a reusable undergarment and a disposable absorbent article. This reusable undergarment has the shape of a panty of lightweight stretchable fabric. It has a seat of fluid resistant material where one or more female receiving grooves are stitched or depressed at a standard spacing that runs transverse to the longitudinal axis of the reusable undergarment seat. A disposable absorbent article of pre determined material is provided with one or more male insert ridges at a standard spacing, which corresponds to that of the female receiving grooves in the seat of the reusable undergarment. The disposable absorbent article is replaced on the reusable undergarment. The undergarment of the '702 disclosure is not a baby diaper. Moreover, the absorbent article has to be entirely replaced. There is no disclosure that involves pulling away a soiled baby diaper to expose a fresh baby diaper.
U.S. Pat. No. 6,336,923 to Fujioka, et al. discloses disposable diapers. This disposable diaper has front and a rear bodies permanently welded together at a crotch zone along a welding line that convexly curves upwardly. Fasteners are formed along side edges of one of the front and rear bodies to enable the bodies to be releasably attached together to form the basic structure of the diaper. An auxiliary liquid absorbent panel is permanently attached to float above the convexly curved welding line of the crotch zone for greater absorbency. This disposable diaper has portions that fit around the legs and waist of the user. The crotch portion has a welded absorbent pad, which is not removed when soiled to expose a fresh pad.
U.S. Pat. No. 7,090,665 to Ohashi, et al. discloses a disposable diaper. This disposable diaper includes an air permeable cover member and a body fluid absorbent member attached to an inner side of the cover member. The absorbent member is composed of a liquid-pervious topsheet, an air permeable backsheet and an absorbent core member disposed therebetween. The absorbent member is formed on a side adjacent the backsheet with at least one first groove concaved in a direction from the backsheet toward the topsheet. This diaper must be opened outwardly and discarded. There is no means provided to quickly remove a soiled diaper while exposing a fresh diaper.
Absorbent composites suitable for use in disposable absorbent garments such as diapers, adult incontinent products, and the like, are known. Such absorbent composites are described, for example, in U.S. Pat. No. 4,699,619 to Bernardin; U.S. Pat. No. 4,798,603 to Meyer et al.; U.S. Pat. No. 4,834,735 to Alemany et al.; U.S. Pat. No. 5,147,343 to Kellenberger; and U.S. Pat. No. 5,149,335 to Kellenberger et al.
Generally, such absorbent composites comprise a means of containing a high-absorbency material and a high-absorbency material. Suitable means for containing the high-absorbency material include fibrous matrixes, such as those formed from air-laid cellulosic fibers or a co-form material comprising cellulosic fibers and meltblown polyolefin fibers. A wide variety of high-absorbency materials (also known as superabsorbent materials) are known to those skilled in the art. See, for example, U.S. Pat. No. 4,076,663 to Masuda et al.; U.S. Pat. No. 4,286,082 to Tsubakimoto et al.; U.S. Pat. No. 4,062,817 to Westerman; and U.S. Pat. No. 4,340,706 to Obayashi et al.
U.S. Pat. No. 4,333,461 to Muller discloses borated polysaccharide absorbents and absorbent products. Guar gum as an exemplification of cis-1,2-diol polysaccharides is first hydrated then thickened by cross-linking with borax and finally dried to powder in flake form, preferably by freeze drying. The resulting particles can absorb up to 100 times their weight or more of aqueous fluids such as urine. Absorbent articles, such as disposable diapers, bandages, and the like are formed with the borax-cross-linked guar gum as absorbent. In a preferred diaper the dry absorbent particles of the borax cross-liked guar gum are placed in the cells of a cellular or bubble-type substrate. The resultant material forms a superabsorbing polymer. No disclosure is contained within the '461 patent concerning use of such a polymer in a baby's double diaper system.
U.S. Pat. No. 4,360,021 to Stima discloses an absorbent article. This absorbent article comprises a cover sheet and a backing sheet. The cover and backing sheets are attached in areas without the use of water-insoluble adhesives to form pockets in which a fluid absorbent material is stored. The absorbent article is formed by depositing portions of the fluid absorbent material on the backing sheet, placing the cover sheet over the absorbent material and the backing sheet, and pressing the cover sheet towards the exposed parts of the backing sheet to cause bonding of the fibers in each sheet and attaching the cover sheet to the backing sheet to form pockets in which the absorbent material is stored. The absorbent material comprises a mixture of (a) a derivatized or underivatized cis-1,2-diol polysaccharide, boric acid and an alkali material or (b) a borate cross-linked guar gum and alkali. This absorbent article is not indicated to be incorporated in a baby diaper.
Notwithstanding the efforts of prior art workers to provide diapers for babies that are easily changeable, there remains a need in the art for a diaper system wherein two diapers are placed one above the other and bonded together with a releasable adhesive, so that the inner soiled diaper may be easily pulled away and discarded to reveal an outer diaper that provides a fresh urine absorbing diaper surface that has not been contaminated by the inner soiled diaper. A diaper with this capability would be extremely useful during traveling or shopping situations, where changing a baby takes substantial time and effort and facilities that accommodate a full diaper change and cleaning operation are limited.